This patent application relates to a breakdown screed plate.
Screeding devices have been used for leveling and consolidating curing concrete. These screeds usually include a horizontal plate which is moved across the surface of the concrete to level the concrete and prepare it for finishing. Vibrators are sometimes used to cause the screed plate to vibrate against the surface of the concrete in order to consolidate it.
Some prior art screeds utilize an internal combustion engine mounted on the screed plate for causing the vibration of the screed plate. These internal combustion engines are heavy and add substantially to the weight of the screed.
Other screed devices utilize an electric motor requiring a cord to extend from the screed to an electrical outlet. These cords often drag on the concrete and deform the surface of the concrete. There is also a safety hazard with electrical cords because the concrete is wet.
Many prior art screed devices have one or more handles for moving the screed plate across the surface of the concrete. Also, it is desirable to adjust the angle of the screed plate relative to the concrete surface. At times it is desirable to lift the leading edge of the screed plate to allow more concrete under the plate for filling low areas. Other times it is desirable to lift the trailing edge of the concrete so that the leading edge cuts into the concrete and removes it from a high spot. A screed plate is normally pulled by the handles toward the operator, and therefore the leading edge is the edge of the screed plate presented toward the operator.
It is often desirable to disassemble the screed plate at the site for cleaning and for transporting. Therefore, an easy way for assembling and disassembling the screeding device is important.
Therefore a primary object of the present invention is the provision of an improved vibrating screed.
A further object of the present invention is the provision of a vibrating screed which is easy to handle in transporting and which may be easily assembled and disassembled with no tools needed.
A further object of the present invention is the provision of an improved screed plate which can be adjusted to any operator's height.
A further object of the present invention is the provision of a vibrating screed which can switch and interchange the handles from right to left or from left to right.
A further object of the present invention is the provision of a vibrating screed which has instant response to a variable speed control switch which utilizes a rechargeable battery pack rather than an internal combustion engine or an electric cord.
A further object of the present invention is the provision of a screed plate which can be angled and tilted easily to accommodate raised portions or lowered portions of the surface of the concrete.
A further object of the present invention is the provision of a screed plate which can sense the height of a beam of light relative to the concrete surface and by so doing determine whether the concrete surface is level, includes rises, or includes lowered portions.
A further object of the present invention is the provision of a vibrating screed plate which can be operated in enclosed areas without causing harmful emission or fumes.
A further object of the present invention is the provision of a vibrating screed plate that will adapt for manual use of a laser for leveling.
A further object of the present invention is a screed plate that has a unique pointed leading edge and an upwardly curved surface above the leading edge for engaging excess concrete.
A further object of the present invention is the provision of an improved screed plate which is economical to manufacture, durable in use, and efficient in operation.